![]() Models able to predict TCP down T with respect to SNR observed were developed and validated for different signal categories. Measurements were taken for multiple users in small offices, open corridors and free space environments using an infrastructure based IEEE 802.11b WLAN while transmitting different quality of service (QoS) traffic. The dependence of TCP downstream throughput (TCP down T) on signal to noise ratio (SNR) has been studied in this paper. ![]() Our models enable network designers and installers to predict the TCPdownT without the need to measure additional parameters other than the observed SNR which is already part of the normal network installation process. Comparing our results with previous work on TCP upstream throughput showed that it is more accurate to investigate upstream and downstream throughput separately. We observed RMS errors of 0.938012 Mbps, 1.047012 Mbps, 0.65833 Mbps and 0.452927 Mbps for the general (all SNR) model, strong signals model, grey signals model and Weak signals model respectively which were much lower than that of similar models with which they were compared. Our findings show a large variation in the throughput behaviour of the IEEE 802.11b WLAN system for the different categories of signals. Models describing TCPdownT against SNR for different signal categories were statistically generated and validated. The study was carried out in small offices, open corridors and free space environments using an infrastructure based IEEE 802.11b WLAN while transmitting different quality of service (QoS) traffic all corresponding to different wireless multimedia tags. This paper presents our study on the dependence of TCP downstream throughput (TCPdownT) on signal to noise ratio (SNR) for multiple users in an IEEE 802.11b Wireless Local Area Network (WLAN) system. Simulation results show that the starvation problem is resolved with our approach, and the target throughput is met. To address this problem, based on our model, we formulate a bandwidth allocation problem to optimize the network throughput and fairness under some predefined requirements by systematically tuning the AP and stations contention windows. ![]() Simulation evaluation shows that our model predicts network performance accurately over a wide range of network sizes and indicates the existence of a throughput starvation problem. Given any number of hidden nodes, only four constraints are needed to describe the interaction between stations and the AP with the consideration of both uplink and downlink traffic. Unlike existing models, our model can accommodate different numbers of hidden nodes without increasing the model complexity. ![]() Motivated by observations from real world wireless local area network (WLAN) deployments, we develop in this paper a novel analytical model to characterize the saturation throughput of an IEEE 802.11-based access point (AP) and stations under the influence of hidden terminals. ![]()
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